Endoscopes for medical use have been adopted for various diagnostic and medical treatment procedures. Endoscopes have been used for the diagnosis and treatment of a wide range of diseases and disorders that often require a physician to access the tortuous and relatively small cross-sectional areas of a patient's internal anatomical body lumens. A patient's pancreaticobiliary system (including the anatomical regions of the gall bladder, pancreas, and the biliary tree), for example, is accessed for diagnosis and/or treatment of disorders of certain portions of the digestive system.
As another example, endoscopes are used with immobilization and retrieval devices for stabilizing and/or removing organic material (e.g., blood clots, tissue, and biological concretions such as urinary, biliary, and pancreatic stones) and inorganic material (e.g., components of a medical device or other foreign matter), which may obstruct or otherwise be present within a body's anatomical lumens. For example, concretions can develop in certain parts of the body, such as in the kidneys, pancreas, and gallbladder. Minimally invasive medical procedures generally involve causing limited trauma to the tissues of a patient and can be used to dispose of problematic concretions. Lithotripsy and ureteroscopy, for example, are used to view and treat urinary calculi (e.g., kidney stones) in the ureter of patients.
One of the most common methods for non-invasively viewing an internal body cavity of a patient is with an imaging endoscope. Such endoscopes are elongated devices that are inserted into the body cavity. Light is delivered through an illumination channel of the endoscope, and reflected light is gathered by one or more lenses that are coupled to an imaging channel. Light from the imaging channel is transmitted out of the endoscope and supplied to a camera or other viewing device so that a physician can examine the internal body tissue.
The internal body portions accessed by an endoscope, however, are remote from atmospheric light. This poor lighting (or even absence of light) within a target treatment portion requires that an endoscope be equipped with an internal light source. Known endoscope systems use an external light source transmitted to the treatment area through an optical fiber, for example. Other known systems present multiple optical fibers in a bundle to provide light at the tip of an endoscope. Such optical fiber light sources present a narrow beam of light illuminating an area directly incident to the path of the light rays emitted from the fibers. In endoscopes having, for example, front/forward directed light sources, the lighting is often ineffective since the only illuminated area is the narrow path directly incident to the direction of the emitted light rays. This arrangement is equated to using a flashlight is a dark cave. Accordingly, there is a need for a supplemental endoscope light source for illuminating a greater area of a treatment location of a patient.
FIG. 1, for example, illustrates a known endoscope system. For purposes of this disclosure, “distal” refers to the end further from the device operator during use and “proximal” refers to the end closer to the device operator during use. FIG. 1 depicts a known endoscope 10 including a flexible outer tube 12 extending between a distal end 14 and a proximal end (not shown) of the device. The distal end 14 of endoscope 10 is illustrated as positioned within a patient's internal body portion, such as, for example, anatomical lumen 18. The endoscope 10 includes an illumination channel 15 housing at least one optical fiber 16 therein.
As seen in FIG. 1, optical fiber 16 emits a distally directed path of light comprising an illumination path 20. As seen in FIG. 1, only the area upon which illumination path 20 impinges is illuminated and therefore viewable by an operator. Therefore, in the illustrated arrangement, only the area in the direct forward path of the endoscope 10 is illuminated for viewing. An area depicted by arrows 22 represents a portion of lumen 18, extending laterally beyond, and proximal away from, the illumination path 20. Accordingly, arrows 22 depict a dark, poorly lit portion of lumen 18. As a result of the relatively narrow area lighted by illumination path 20, only a small forwardly directed portion of lumen 18 is viewable by the operator.
The optical fiber 16 extends within an illumination channel 15 of the endoscope for emitting light at the treatment region of an endoscope. In use, optical fibers and their housing lumens occupy a portion of the available area of the endoscope. An alternative light source could eliminate the need for optical fibers and illumination channels, thereby decreasing the outer diameter of the endoscope. Accordingly, there is a need for an improved alternative endoscope light source that overcomes the disadvantages of optical fibers and provides a reduced size for a combined medical device and light source.